Over the past few years a lot of different information visualization techniques have been proposed. Being a relatively new and large field, the spectrum of emerging techniques has not clearly been identified. Another major consequence of the youthfulness of the field is that very few evaluation have been conducted so far. The aim of the panel will be to address these two points. First, panelist will characterize the spectrum of information visualization technology depending on tasks, users or data. Panelists will further discuss future trends in visualization technology by determining which are the most important features or challenges that information visualization systems should address. Second, the discussion will focus on how these systems are to be evaluated: through controlled experiments, system evaluation, long-time studies, verbal protocols, theoretical evaluations, or else?

Tight coupling is a strategy in the design of query mechanisms in direct manipulation query systems. Tight coupling helps users navigate toward high precision queries in a space of database queries, avoid empty query results, and quickly narrow down the number of possible and meaningful queries. Tight coupling of a query mechanism is defined as: the results of user operations (querying, zooming, panning) on query devices (starfields, rangesliders, alphasliders, and toggles) are reflected in all query devices by visual feedback and physical constraints on meaningful query settings. An intuitive design of tight coupling is presented, along with a formal description. The design is based on a Model of Information Exploration -- MIE. An empirical study in which subjects interacted with a tightly coupled interface to a jobs/skills matching database confirms the power of tight coupling.

This paper offers new principles for visual information seeking (VIS). A key concept is to support browsing, which is distinguished from familiar query composition and information retrieval because of its emphasis on rapid filtering to reduce result sets, progressive refinement of search parameters, continuous reformulation of goals, and visual scanning to identify results. VIS principles developed include: dynamic query filters (query parameters rapidly adjusted with sliders, buttons, maps, etc.), starfield displays (two-dimensional scatterplots to structure result sets and zooming to reduce clutter), and tight coupling (interrelating query components to preserve display invariants and support progressive refinement combined with an emphasis on using search output to foster search input). A FilmFinder prototype using a movie database demonstrates these principles in a VIS environment.

Research has suggested that rapid, serial, visual presentation of text (RSVP) may be an effective way to scan and search through lists of text strings in search of words, names, etc. The Alphaslider widget employs RSVP as a method for rapidly scanning and searching lists or menus in a graphical user interface environment. The Alphaslider only uses an area less than 7 cm x 2.5 cm. The tiny size of the Alphaslider allows it to be placed on a credit card, on a control panel for a VCR, or as a widget in a direct manipulation based database interface. An experiment was conducted with four Alphaslider designs which showed that novice Alphaslider users could locate one item in a list of 10,000 film titles in 24 seconds on average, an expert user in about 13 seconds.

We designed, implemented and evaluated a new concept for direct manipulation of databases, called dynamic queries, that allows users to formulate queries with graphical widgets, such as sliders. By providing a graphical visualization of the database and search results, users can find trends and exceptions easily. Eighteen undergraduate chemistry students performed statistically significantly faster using a dynamic queries interface compared to two interfaces both providing form fill-in as input method, one with graphical visualization output and one with all-textual output. The interfaces were used to explore the periodic table of elements and search on their properties.